Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description must fully disclose behavior. It only states the action and PIN format, but omits critical mutation details such as permission requirements, side effects (e.g., invalidating sessions), error behavior, or reversibility.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The opening sentence is duplicated verbatim, which is unnecessary waste. Parameter documentation is useful, but the repetition and a typo ('but be' instead of 'must be') reduce the overall conciseness and polish.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description covers the purpose, parameters, and return type, but with empty annotations and no output schema details it lacks context on error handling, security requirements, or behavioral outcomes. It is minimally adequate but not comprehensive.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. It does this effectively by documenting all four parameters, including their source (api_key, token, wallet_fk) and the format for new_pin, adding meaning beyond the raw schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description states a specific action ('Changes the wallet PIN') with a clear constraint ('must be 5 digits'), making the purpose unambiguous. This clearly distinguishes it from other access-related tools like pause or login.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives useful context by noting that token and wallet_fk come from /access/login, implying a prerequisite. However, it does not explicitly state when to use this tool versus alternatives, nor provide exclusions or alternative tool recommendations.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.